The ignition of the fuel in a combustion chamber causes very harsh and adverse conditions which can cause a glow plug to deteriorate. Also byproducts of combustion can accumulate on a glow plug causing fouling and blocking the glow plug from igniting the fuel. In the combustion chamber conditions progress from being almost completely full of liquid fuel, to varying fuel air mixtures, to partial combustion, to full combustion and then to full exhaust. The position of the glow plug is therefore of very great significance for ignition in such burners to avoid deterioration and fouling of the glow plug and still ignite the fuel or fuel-air mixture. The position of the glow plug is also of very great significance for an optimal ignition process in such burners. Previously the glow plug was arranged in a socket projecting radially away from the circumferential wall of the combustion chamber, or it was positioned behind the bottom of the combustion chamber.